How fast does light travel?

Answer 1

One important thing to know about light is that it travels and behaves as waves. Light also has the character of a particle, but we're going to just look at some basic stuff about light as a wave.
All light travels in the form of waves at a speed of about 300,000 (300 thousand) kilometers per second in a vacuum such as space. That's about 186,000 miles every second. That means light can travel almost eight times around the Earth in a second. That's pretty fast! Light has slightly slower speeds when it travels through denser material such as a planet's atmosphere or a piece of glass
There are many different kinds of light besides the one you can see. What do you think is a good word to describe the light you see? Scientists often describe the light you can see as "visible" light. The entire range of different kinds of light including the ones the human eye cannot see is called the electromagnetic spectrum. Can you think of some other types of light besides visible light? You'll be trying to figure out the different types of light that make up the electromagnetic spectrum as you go through this light tour!

Answer 2

How Fast Does Light Travel

Answer 3

In short: No. Nothing can travel faster than light that we know of or can prove yet. If you want a longer, more comprehensive answer then: One way I think about these kinds of problems is to think about motion. Basically if you have two points of a set distance, lets say A and B. If we travel from A to B at a set speed we it will take a set amount of time. Now if we travel from A to B at a faster speed, the time it takes will be less. So really the faster you go, the the slower your perception of time (this is called time dilation). Now what if you continue to increase your speed, faster, until you reach the speed of light. In theory the time should get shorter and shorter until you reach a point where you should cross over and then start travelling back in time (as time reverses)! This of course is completely hypothetical, as Einstein's special theory of relativity tells us nothing can travel faster than the speed of light. If you want to know why, there are several reasons. If you take Einstein's equation: E=mc^2 it is only the short form, the full equation is actually: E = mc^2/squreroot(1 - v^2/c^2) and this tells us that mass and energy are the same thing in different forms and can be converted between each other. The equation also tells us that as velocity (speed in a direction) increases - and approaches infinity you would need an infinity amount of energy! We can't produce infinity energy and so can't accelerate a mass faster than light! That's the simpler explanation, unless you want to start considering more physics and advanced theories! The last point about your question is that if you are just concerned with reaching a point faster than light, there are other theory's on how to achieve this - i.e. wormholes, etc, but that then becomes advanced physics again! Although much of this is considered quite disprovable theory we are always discovering new things (and particles) all the time, so there is always a possibility that theories can change, that's just how science works. So we may discover something new! :-)

Answer 4

Light travels at a speed of 299,792 kilometers per second; 186,287 miles per second. It takes 499.0 seconds for light to travel from the Sun to the Earth, a distance called 1 Astronomical Unit. below I list the light travel times from the Sun to each planet:

Answer 5

Electromagnetic waves, including visible light, travels at a speed of 2.997925 x 10^8 m/s in vacuum. In other media, its speed depends on refractive index of the material.

Answer 6

Speed of light

The speed of light in a vacuum is exactly 299,792,458 meters per second (fixed by definition). Although some people speak of the "velocity of light", the word velocity is usually reserved for vector quantities, which have a direction.

The speed of light has been measured many times, by many physicists. The best early measurement in Europe is by Ole Rømer, a Danish physicist, in 1676. By observing the motions of Jupiter and one of its moons, Io, with a telescope, and noting discrepancies in the apparent period of Io's orbit, Rømer calculated that light takes about 18 minutes to traverse the diameter of Earth's orbit. If he had known the diameter of the orbit in kilometers (which he didn't) he would have deduced a speed of 227,000 kilometres per second (approximately 141,050 miles per second).

The first successful measurement of the speed of light in Europe using an earthbound apparatus was carried out by Hippolyte Fizeau in 1849. Fizeau directed a beam of light at a mirror several thousand metres away, and placed a rotating cog wheel in the path of the beam from the source to the mirror and back again. At a certain rate of rotation, the beam could pass through one gap in the wheel on the way out and the next gap on the way back. Knowing the distance to the mirror, the number of teeth on the wheel, and the rate of rotation, Fizeau measured the speed of light as 313,000 kilometres per second.

Léon Foucault used rotating mirrors to obtain a value of 298,000 km/s (about 185,000 miles/s) in 1862. Albert A. Michelson conducted experiments on the speed of light from 1877 until his death in 1931. He refined Foucault's results in 1926 using improved rotating mirrors to measure the time it took light to make a round trip from Mt. Wilson to Mt. San Antonio in California. The precise measurements yielded a speed of 186,285 mi/s (299,796 km/s [1,079,265,600 km/h]). In daily use, the figures are rounded off to 300,000 km/s and 186,000 miles/s.

Answer 7

so many gave the suggesion for the light travels
but widly accept is
aproximately =to 3*(10^8)

Answer 8

3 x 10^8 m/sec

Answer 9

the speed of light as a physics student is 3X10^8m/s. However for your convenience it is 3,00,000 or 3 lakhs km/s.

Answer 10

300,000 Kilometers per second